Following the launch of their scheme to charge customers for plastic bags, Marks & Spencer announced this week that they have reduced bag usage by 80 per cent, saving 100 million carrier bags from landfill sites and in doing so raised £500,000 for environmental charity Groundwork.

A spokesperson for M&S said, "Our customers have made a major impact already, but there is more work that we can do. What we have achieved so far is a really powerful way to encourage even more M&S customers to change their behaviour and stop using single-use carrier bags."

This week also saw another major retailer, WHSmith move to scrap free plastic bags in all its stores by the end of this month after a successful pilot in the Midlands. Customers will be charged 1p for each bag they use.